Formula Generator options can be used to speed up calculations, restrict the number of possible formulas and set the charge state and polarity.

Parameter Settings:

Charge: Charge state and polarity

Nitrogen rule: Decide whether or not to use the nitrogen rule in the elemental composition calculation. If yes, the choices include even-electron (e.g. radical-cation) or odd-electron (e.g. protonated) ion

Hydrogen Count: Allows you to specify whether an algorithm for the exclusion of implausible formulas with improbable high numbers of hydrogens should be used

Valence Test: Allows you to specify whether formulas should be excluded if the atoms cannot be connected in any way using valences common in organic chemistry

Ring plus Double Bond Equivalent (RDBE): Only formulas will be displayed for which RDBE is within the range From – To. RDBE limits the calculated formulas to those which make sense chemically.

Elements in Use: This tab allows you to specify isotopes of particular elements with a maximum number that will be considered for the calculation of formulas